feat(course): build out all 27 modules, capstone, scaffold, and conventions

Scaffold the course repo and author the full curriculum in dependency-chain
order, following the settled build decisions in handoff.md.

- Scaffold: course README, vendor-neutral AGENTS.md (dogfoods Module 5),
  _TEMPLATE.md (the fixed 9-section module shape), root .gitignore, ship config.
- Modules 1-2: reference exemplars (locked for tone/depth/lab style).
- Modules 3-27: full lessons + runnable labs, each following the template,
  respecting the chain, vendor/model-agnostic, with "feel the pain" labs.
- Module 8 hosting comparison web-researched and date-stamped (as of 2026-06-22),
  not written from memory; expansion-zone modules carry Verify-before-publish.
- Capstone: the full loop end to end on the running tasks-app example.

Lab code syntax-checked (Python/shell/YAML); every module has the 7 core
template sections.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01TfzV5QvtPDz8LJS3Pu5VLT

modules/26-orchestrating-multiple-agents/lab/orchestration-plan.md

@@ -0,0 +1,45 @@
+# Coordination plan — Module 26 lab
+
+This is the artifact orchestration runs on. With one agent, the plan lived in your head. With a
+fleet, it has to live here — because your head doesn't scale and it forgets (Module 2).
+
+Fill the **Status** column as you go, and answer the questions at the bottom. The plan is the
+deliverable, not the code.
+
+---
+
+## The fleet
+
+| Issue | Branch | Worktree | Files owned | Depends on | Status |
+|-------|--------|----------|-------------|------------|--------|
+| #42 count | `feature/42-count` | `tasks-app-42-count` | `cli.py` (dispatch + new fn) | — | queued |
+| #43 docs  | `feature/43-docs`  | `tasks-app-43-docs`  | `README.md`, `CHANGELOG.md` | — | queued |
+| #44 clear | `feature/44-clear` | `tasks-app-44-clear` | `cli.py` (dispatch + new fn) | — | queued |
+
+`main` is reserved as the integration point. No agent works in the main worktree.
+
+---
+
+## Part A — Predict the conflicts BEFORE you launch
+
+Read the "Files owned" column. Which pairs are genuinely parallel, and which will collide at merge?
+Write your prediction here, then watch it come true in Part C.
+
+- Genuinely parallel (disjoint files, no shared interface): _______________________
+- Will collide at merge (and on which file/line): _______________________________
+- If you wanted to avoid the collision, what would you change? (serialize one? scope it to a
+  different file?) _____________________________________________________________
+
+---
+
+## Part D — Score the orchestration honestly
+
+- **Did parallel beat sequential?** Agent wall-clock (overlapping) + your serial review time +
+  conflict resolution, vs. "I'd have done these three myself, in order."
+  Answer: ______________________________________________________________________
+
+- **Which split was worth it and which wasn't?**
+  Answer: ______________________________________________________________________
+
+- **Where was the bottleneck?** (Almost certainly your review queue, not the agents. Name it.)
+  Answer: ______________________________________________________________________